This invention relates to an ion implantation apparatus for injecting an ion beam into a substrate.
On injecting an ion beam into a substrate or a wafer, the substrate may be directed to the ion beam and two-dimensionally moved so that the substrate is entirely scanned by the ion beam.
In a conventional ion implantation apparatus of the type described, an ion beam is emitted onto a substrate along a predetermined direction which may be called an irradiating direction hereinunder. More particularly, the conventional implantation apparatus comprises a supporting section for supporting the substrate and a controlling section for controlling the supporting section to entirely irradiate the substrate by the ion beam.
The supporting section has a disc section for locating the substrate thereon. The disc section is controlled by the controlling section so that the substrate is scanned by the ion beam.
To this end, the disc section is rotated around a first axis parallel to the irradiating direction of the ion beam. Furthermore, the disc section is slidably moved along a second axis substantially perpendicular to the first axis. Thus, the substrate can be entirely irradiated by the ion beam.
In this event, it is to be noted that the ion beam is emitted to the substrate at an invariable incident angle in the conventional ion implantation apparatus. For example, such an invariable incident angle may be a right angle. At any rate, the ion beam is kept at a constant angle.
However, it has been found out that the conventional implantation apparatus is not sufficient to uniformly inject the ion beam to a whole of the substrate.